A number of on-line communication protocols exist that enable users to create network identities and communicate with each other. For example, on the Internet, MICROSOFT MESSENGER messaging service, AOL INSTANT MESSENGER messaging service, SKYPE messaging service, and GOOGLETALK messaging service each provide some level of communication between their users as well as some presence information. However, communication between these competing systems has often been problematic. For example, these applications each maintain their own namespaces, even though they may support identical modes of communication (voice, say, or text IM), and they generally do not interoperate.
Some attempts have been made to utilize services or protocols that interconnect the separate services such that communication can be made between services. TRILLIAN messaging service and JABBER messaging service are attempts that have been made to allow inter-service communication with limited success. Moreover, the management of user identities is still not yet truly unified.